The present embodiments relate to a magnetic resonance device having a motion detection unit and a method for detecting a movement of a patient during a magnetic resonance examination.
A magnetic resonance imaging session may include a plurality of transmit-receive cycles that are assembled into an image by a postprocessing operation. In the case of moving regions of a patient's body that are due, for example, to a heartbeat and/or breathing of the patient, the image acquisition is to take place in the same phase of the movement. Trigger signals for the magnetic resonance imaging are derived from the bodily movement. The trigger signals specify a trigger time instant for the image acquisition or, image data that has been acquired during an undesired movement of the patient is also discarded.
External measurement devices have been used in the prior art for registering a movement of the patient. For example, a respiratory cushion, which measures the respiratory motion based on a change in air pressure, is used to detect a respiratory motion of the patient during a magnetic resonance imaging session. A further example is the use of electrodes in order to detect a cardiac motion of the patient during a magnetic resonance imaging session. However, these external measurement devices are very cost-intensive and, in addition, entail a high level of preparation effort on the part of operating staff overseeing the magnetic resonance imaging session, such as appropriate attachment of the external measurement device to the patient, for example.